Abstract: Perfusion guard is a first of a new generation of devices for interventional cardiology. It encompasses an improved debris collection system with a novel perfusion system. It uses an occlusive balloon to provide total protection from debris from interventional procedures. Distal perfusion is maintained using a variety of endogenous or exogenous perfusion substances delivered through an isolated lumen. These substances may be the patients' blood, artificial blood substitutes or biocompatible perfusion fluids. A therapeutic device or catheter may be introduced through a separate port or may be modified to be delivered over the device. Thus the device provides a safe and improved means of carrying out interventions while protecting from debris generated from these procedures and maintaining perfusion to the segments beyond the site of intervention.